Pyrazolone debivatives



Patented Dec. 9, 1941 PYRAZOLONE DERIVATIVES Hans Zischler, Bitterfeld, Germany, assignor, by mesne assignments, to General Aniline & Film Corporation, New York, N. Y., a corporation of Delaware No Drawing. Application August 9, 1939, Serial No. 289,173. In Germany August 20, 1938 6 Claims.

A known process for making pyrazolone derivatives consists in causing a fl-keto-carboxylic acid ester to react with hydrazine, aryl hydrazine or alkyl hydrazine.

This invention relates to the production of N- (D-aIkyI-sulfonic acid pyrazolone derivatives of the general formula 2 wherein R=alkyl, for instance methyl-, ethyl-, buty1'-, hexyl-, stearyl-, stearoyl, aryl, for instance phenylor naphthyh, or aralkyl for instance benzyl and R'=alkylene or hydroxalkylene by condensing an aromatic or aliphatic fi-keto-carboxylic acid ester with a hydrazinoalkylsulfonic acid.

The hydrazinoalkylsulfonic acids may be made by the process described in U.S. patent application Ser. No. 289,172 filed by Gustav Wilmanns and the present applicant on August 9, 1939 by reacting hydrazinehydrate with alkylenesulfonic acids for instance when hydrazine hydrate is added to ethane sulfonic acid, hydrazinoethane sulfonic acid is obtained. Thus 1 mol of sodium vinyl sulfonate is dissolved in 600 cc. of water, the solution mixed with 100 cc. of hydrazine hydrate and the mixture heated for six hours on the steam bath. To removethe excess of hydrazine, 1 mol of benzaldehyde is added and the benzalazine then formed is filtered. Another mol of nzaldehyde is added and the benzaldehyde compound of the hydrazine ethane sulfonic acid is precipitated, by acidifying with concentrated hydrochloric acid, in the form of crystals melting at 200 C. The free sulfonic acid may be obtained by mixing 1 mol of the benzaldehyde compound with 100 cc. of concentrated hydrochloric acid and steam distilling the mixture.

The hydrazine compounds are generally isolated in the form of their benzaidehyde addition products.

I have further found, that it is not necessary to isolate the free hydrazino alkylsulfonic acids but that the solutions obtained by splitting the benzal-compounds thereof can be used. The process therefore is of considerable advantage in view of its simplicity.

The pyrazolone derivatives thus obtained are valuable intermediate products, for instance for making dyestuifs, particularly such as are of importanu in producing color pictures by color forming development, the dyestufi component being present either in the photographic layer in which case it is rendered fast to diffusion by suitable substitution, or in the developer.

The term monovalent hydrocarbon radical as used herein has the meaning usual inthe art, 1. e. a radical consisting of carbon and hydrogen.

1 The following examples illustrate the invent on:

Example 1 An aqueous suspension of the benzaldehyde compound of hydrazino ethyl sulfonic'acid of the formula SOaH-C HaCHaNHN=CHC 'NOOC come 0 00,115

and the mixture is boiled under reflux for 6 hours. On' cooling the 3-(para-nitrophenyD- pyrazolone-(5)-l-ethane sulfonic acid of the formula I t-z? separates in the form of a yellow crystalline magma the course of the reaction may be graphically depicted as follows:

B0;H CH:CHiNHN=CH-C souT-omcmNHNH t Example 2 By using acetoacetic acid ester instead of paranitrobenzene acetic ester in the process of Example 1 there is obtained 3-methy1pyrazolone-(5)- 1 -ethane,sulfonic acid of the formula oHg- -cm CHlCHrSOaH Example 3 By using stearylacetic acid ester of the formula 'cnrnscocmcooczns instead of para-nitrobenzoylacetic acid ester in theprocess of Example 1 there is obtained 3-heptadecylpyrazolone-(5)-1- 7 ethane-sulfonic-acid of the formula C Hui? N HzCHzSOaH Example 4 An aqueous suspension of 1 mol of the benzaldehyde compound of 1 hydrazino-Z-liydroxypropane-Zi-sulfonic acid of the formula SOaH.CHz.0H.CH.CHz.NHN=CH-C is steam-distilled after the addition of enough acid, until no more benzaldehyde passes over. To the solution thus obtained there is added an alcoholic solution of 1 mol p-nitrobenzoylacetic acid ester and the solution is heated under reflux for several hours. On cooling 3-(paranitrophenyl) pyrazolone-(5) 1 propano1-(2')- sulfonic acid-(3') of the formula NOr-C CCH: V 1 1 N emotion-unison separates.

' Example If instead of para-nitrobenzoylacetic acid ester there is used in Example 4 acetoacetic acid ester, there is obtained 3-methylpyrazolone-(5) -1-propanol-(2)-sulfonic acid-(3') oi the formula Example 6 It instead or para-nitrobenzoylacetie acid ester there is used in Example 4 stearylacetic acid ester there is obtained 3-heptadecylpyrazolone-(5) -1- propanol-(2) -sulfonic acid-(3') or the formula pounds which comprises reacting the aqueous solution obtained by splitting with acid the benzal compound of a primary hydrazine monoalkylsulionic acid having at least two carbon atoms in the alkyl group, said alkyl group being taken from the class consisting of alkyl hydrocarbon radicals and hydroxy alkyl radicals, and steam distilling with an acyl acetic acid ester.

3. A compound having the following general lormula:

H|CCR iv-som wherein R is selected from theclass consisting of monovalent hydrocarbon radicals and nitro-aryl radicals, R. is an alkylene group having at least .two carbon atoms, said alkylene group being taken from the class consisting of alkylene hydrocarbon radicals and hydroxy alkylene radicals.

4. 3-methylpyrazolone (5) 1 -ethane-sulfonic acid.

5. 3-heptadecylpyrazolone -(5) 1 ethane-sulionic acid.

6. 3- (para-nitrophenyl) -pyrazolone- (5) -1-propanoi-(2) sulfonic acid (3') HANS ZISCHLER. 

